Question

在我的观看扩展代理init功能中，我在WCSession上设置了KVO观察员：

if WCSession.isSupported() {
  let defaultSession = WCSession.default
  defaultSession.addObserver(self, forKeyPath: "activationState", 
                             options: [.old, .new], 
                             context: &ExtensionDelegate.wcSessionKVOcontext)
  defaultSession.addObserver(self, forKeyPath: "hasContentPending", 
                             options: [.old, .new], 
                             context: &ExtensionDelegate.wcSessionKVOcontext)
}

为了完成所有观看后台任务，这将调用函数

  override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {
    if context == &ExtensionDelegate.wcSessionKVOcontext {
      printStatusChanges(keyPath: keyPath, change: change)
      DispatchQueue.main.async {
        self.completeAllTasksIfReady()
      }
    }
  }

带

  private func completeAllTasksIfReady() {
    let session = WCSession.default
    // the session's properties only have valid values if the session is activated, so check that first
    if session.activationState == .activated && !session.hasContentPending {
            if wcBackgroundTasks.isEmpty {
                print("No background tasks")
            } else {
                wcBackgroundTasks.forEach { $0.setTaskCompleted() }
                print("\(wcBackgroundTasks.count) connectivity background tasks completed")
            }
      wcBackgroundTasks.removeAll()
    }
  }

通常，这很好用但是我遇到了以下日志崩溃：

Thread 0 name:  Dispatch queue: com.apple.main-thread
Thread 0 Crashed:
0   libsystem_kernel.dylib          0x1db2eda8 __abort_with_payload + 24
1   libsystem_kernel.dylib          0x1db2ae60 abort_with_payload_wrapper_internal + 60
2   libsystem_kernel.dylib          0x1db2ae24 abort_with_payload_wrapper_internal + 0
3   WatchKit                        0x2ddfce86 -[WKRefreshBackgroundTask setTaskCompleted] + 414
4   Watch Extension                 0x00037258 closure #1 in ExtensionDelegate.completeAllTasksIfReady() + 209496 (ExtensionDelegate.swift:196)
5   Watch Extension                 0x000372b0 thunk for @callee_guaranteed (@owned WKRefreshBackgroundTask) -> (@error @owned Error) + 209584 (ExtensionDelegate.swift:0)
6   Watch Extension                 0x0003af08 partial apply for thunk for @callee_guaranteed (@owned WKRefreshBackgroundTask) -> (@error @owned Error) + 225032 (ExtensionDelegate.swift:0)
7   libswiftCore.dylib              0x00525350 0x2fc000 + 2265936
8   libswiftCore.dylib              0x00433b7c 0x2fc000 + 1276796
9   libswiftCore.dylib              0x00304060 0x2fc000 + 32864
10  Watch Extension                 0x00036eec ExtensionDelegate.completeAllTasksIfReady() + 208620 (ExtensionDelegate.swift:196)
11  Watch Extension                 0x000350d4 closure #1 in ExtensionDelegate.observeValue(forKeyPath:of:change:context:) + 200916 (ExtensionDelegate.swift:108)
12  Watch Extension                 0x0000993c _T0Ieg_IeyB_TR + 22844 (AlertManager.swift:0)
13  libdispatch.dylib               0x1d9d3456 _dispatch_call_block_and_release + 10
14  libdispatch.dylib               0x1d9d3432 _dispatch_client_callout + 6
15  libdispatch.dylib               0x1d9e3604 _dispatch_main_queue_callback_4CF$VARIANT$mp + 858
16  CoreFoundation                  0x1df7db1e __CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE__ + 10
17  CoreFoundation                  0x1df7b73c __CFRunLoopRun + 932
18  CoreFoundation                  0x1dec7660 CFRunLoopRunSpecific + 534
19  GraphicsServices                0x1fb7ab3e GSEventRunModal + 94
20  UIKit                           0x24746604 UIApplicationMain + 156
21  libxpc.dylib                    0x1dcf7b14 _xpc_objc_main + 586
22  libxpc.dylib                    0x1dcf94a8 xpc_main + 154
23  Foundation                      0x1e9b2cf2 service_connection_handler + 0
24  PlugInKit                       0x2525c06e -[PKService run] + 676
25  WatchKit                        0x2de1b036 main + 162
26  libdyld.dylib                   0x1da2e782 start + 2

显然，在其中一个setTaskCompleted任务中调用WKRefreshBackgroundTask时会发生崩溃。

但是可能是什么原因，或者如何调试它？

watchOS后台任务在setTaskCompleted上崩溃

0 个答案: